Human Physiology/Pregnancy and birth - Wikibooks, open books for an open world
Your body goes through lots of changes - physical and emotional - during the first trimester of pregnancy. Here's an overview of what you can. 'important roles to play in health education and in counselling women, their families The Mother's developing Relationship with the Fetus/Baby .. associated with significant changes to fetal/infant physiology and behaviour, and long-term. During pregnancy, the physiological alteration of hormonal patterns is the main Respiratory function does not differ between singleton and twin pregnancies . . interruption on the diaphragm and their relation to pulmonary tuberculosis.
However, nutrient deficiencies are generally found in low-SES populations, where they are more likely to involve multiple rather than single deficiencies 2 ; and studies that address and bring together the broader picture of multiple nutrient intakes or deficiencies are lacking.
Respiratory physiology of pregnancy
In this review, our intention is to provide a broad multinutrient and multifactorial overview of the literature regarding maternal nutrition and birth outcomes. Given the breadth of the topic, we limit our focus to the 3 major adverse birth outcomes: We do not cover pregnancy complications e. We included primarily studies published from onward; however, where we deemed it important, occasionally studies published earlier than were also included.
We focused mainly upon the evidence from observational studies of maternal dietary intake and birth outcomes, because reviews of randomized controlled trials RCTs are plentiful and need not be replicated.
The observational literature, however, has been less extensively reviewed. Thus, our intention in this review is to bring together the main observational evidence in this field to provide a parallel resource that can be viewed together with the evidence from RCTs, in an effort to better understand associations between maternal nutrition and birth outcomes. We also discuss secondary factors, many of a methodological or study-design nature, that may lead to inconsistent findings, as well as the theory and evidence regarding the role of SES factors in the maternal nutrition-birth outcome association.
Low birth weight is defined as a birth weight less than 2, g; it can result from premature delivery, intrauterine growth failure or disruption, or a combination of the two 5. In both developed and developing countries, low birth weight is strongly associated with perinatal morbidity and increased risk of long-term disability 5. The more healthy and relaxed the mother is, the better it will be to cope with the demands of pregnancy. A healthy lifestyle combines many factors: Balanced Diet A poor diet can cause a low birth weight.
Excessive weight gain during pregnancy can cause back problems, varicose veins, or indicate preclampsia. Advice on diet often includes to eat foods that are high in nutritional content. Sufficient protein, vitamins, carbohydrates, fats, and minerals, as well as fiber. Limit intake of saturated fats and sugar, and salt. Drink plenty of fluids. Regular Exercise Mild exercise, such as walking or swimming, is beneficial and will help cope with the workload of pregnancy and the demands of labor.
Mother's should listen to her body and stop exercising when it tells her to. Exercise should never be painful. Baby's Health Smoking reduces the oxygen and nutrients passing via the placenta to the baby. Avoid alcohol to avoid serious birth defects.
In vitro Fertilization and Artificial Implantation[ edit ] Oocyte is injected with sperm outside of the womb. An alternative when other methods of achieving contraception have failed. In vitro fertilization IVF is a technique in which egg cells are fertilized by sperm outside the woman's womb. IVF is a major treatment in infertility when other methods of achieving conception have failed. The process involves hormonally controlling the ovulatory process, removing ova eggs from the woman's ovaries and letting sperm fertilize them in a fluid medium.
The fertilized egg zygote is then transferred to the patient's uterus with the intent to establish a successful pregnancy. The term in vitro, from the Latin root, is used, because early biological experiments involving cultivation of tissues outside the living organism from which they came, were carried out in glass containers such as beakers, test tubes, or petri dishes.
While the overall live birth rate via IVF in the U. Other factors that determine success rates include the quality of the eggs and sperm, the duration of the infertility, the health of the uterus, and the medical expertise. It is a common practice for IVF programmes to boost the pregnancy rate by placing multiple embryos during embryo transfer. A flip side of this practice is a higher risk of multiple pregnancy, itself associated with obstetric complications. Embryo cryopreservation If multiple embryos are generated, patients may choose to freeze embryos that are not transferred.
Those embryos are placed in liquid nitrogen and can be preserved for a long time. There are currentlyfrozen embryos in the United States.
Respiratory physiology of pregnancy
The advantage is that patients who fail to conceive may become pregnant using such embryos without having to go through a full IVF cycle. Or, if pregnancy occurred, they could return later for another pregnancy.
Embryonic stem cells[ edit ] Pluripotent, embryonic stem cells originate as inner mass cells with in a blastocyst. The stem cells can become any tissue in the body, excluding a placenta.
Only the morula's cells are totipotent, able to become all tissues and a placenta. Embryonic celtic cell lines ES cell lines are cultures of cells derived from the epiblast tissue of the inner cell mass ICM of a blastocyst. A blastocyst is an early stage embryo - approximately 4 to 5 days old in humans and consisting of cells.
ES cells are pluripotent, and give rise during development to all derivatives of the three primary germ layers: In other words, they can develop into each of the more than cell types of the adult body when given sufficient and necessary stimulation for a specific cell type.
They do not contribute to the extra-embryonic membranes or the placenta. This means they can become any kind of human tissue ie. When given no stimuli for differentiation, ES cells will continue to divide in vitro and each daughter cell will remain pluripotent. The pluripotency of ES cells has been rigorously demonstrated in vitro and in vivo, thus they can be indeed classified as stem cells. Because of their unique combined abilities of unlimited expansion and pluripotency, embryonic stem cells are a potential source for regenerative medicine and tissue replacement after injury or disease.
To date, no approved medical treatments have been derived from embryonic stem cell research. This is not surprising considering that many nations currently have moratoria suspension of practices on either ES cell research or the production of new ES cell lines.
There exists a widespread controversy over stem cell research that emanates from the techniques used in the creation and usage of stem cells. Opponents of the research argue that this practice is a slippery slope to reproductive cloning and tantamount to the instrumentalization of a human being.
Contrarily, some medical researchers in the field argue that it is necessary to pursue embryonic stem cell research because the resultant technologies are expected to have significant medical potential, and that the embryos used for research are only those meant for destruction anyway as a product of in vitro fertilization.
This in turn, conflicts with opponents in the pro-life movement, who argue that an embryo is a human being and therefore entitled to dignity even if legally slated for destruction. The ensuing debate has prompted authorities around the world to seek regulatory frameworks and highlighted the fact that stem cell research represents a social and ethical challenge.
Reproductive Cloning Reproductive Cloning is a technology used to generate an animal that contains the same nuclear DNA as another currently or previously existing animal. Scientists transfer the genetic material from the nucleus of a donor adult cell to an egg whose nucleus, and thus its genetic material has been removed.
The egg containing the DNA, now reconstructed, has to be treated with chemicals or electric current in order to stimulate cell division.
Once the cloned embryo reaches a suitable stage, it is transferred to the uterus of a female host to continue development until birth. Currently this is illegal to practice in the United States. Therapeutic Cloning Recent research by researchers led by Anthony Atala of Wake Forest University and a team from Harvard University has found that amniotic fluid, in addition to its main functions of cushioning a growing fetus and providing buoyancy, is also a plentiful source of non-embryonic stem cells.
These cells have demonstrated the ability to differentiate into a number of different cell-types, including brain, liver and bone. Therapeutic Cloning refers to a procedure that allows the cloning of specific body parts and organs to be used for medical purposes. Although this has not been realized, much research is being done on the subject.
Pregnancy and Lactation[ edit ] A mother's milk is ideal because it meets the baby's specific needs. Lactation is a neuroendocrine response in milk production. Sucking stimulates the sensory nerve endings in the nipples and sends stimulus to the hypothalamus. The hypothalamus stimulates anterior pituitary and prolactin is released. In milk let-down the sucking stimulates sensory nerves in the nipples. This stimulates the hypothalamus which then stimulates the posterior pituitary and releases oxytocin.
Sucking also stimulates contraction of the cells around the alveoli in the mammary cells. Milk then flows into the milk ducts causing milk let-down. Breast milk provides all the nutrients required for the first months. It contains carbohydrates such as lactosefats such as linoleic acidand easily digestible proteins such as alpha-lactalbumin.
Breast milk also contains an adequate supply of vitamins and minerals, digestive enzymes, hormones and immunological factors.
The first milk produced after birth is called colostrum.
This is synthesized during the end of pregnancy and days of postpartum. It is very high in protein and low in fat and carbohydrates, and contains immunoglobulins. This help the baby have a first bowel movement and prevent jaundice. The bowel movement that results from the colostrum is a different color and consistency than future bowel movements once the mother's milk comes in. In some cultures the colostrum is discarded because of the difference, but what they do not know is that it is the best thing for the baby.